At present, there are devices and systems that can detect and count human traffic, in shopping malls or terminal stations of various public transportation vehicles. These systems make use of overhead sensors across wide aisles of several meters or machine vision algorithms to interpret camera images.
However, these conventional systems are mainly used to gather passenger or consumer preference statistics and are not for use in controlling automatic fare gates.
Systems that are used to monitor and control fare gates may employ underfoot (carpet) sensors or light beams. On the other hand, simpler systems may utilize light sensors only as a safety measure against closing a barrier on a person and to monitor entries and exits via the fare gates.
The prior art cited have the disadvantages of being costly and are complex to maintain. Systems utilizing camera systems also require sufficiently bright lighting. The idea of being captured visually by cameras may be considered intrusive by some people. Systems employing underfoot detectors have the disadvantage in high mechanical wear and tear of the detectors.
Currently, a fare gate system used is that of a passenger with a valid fare card activating the opening of the barrier of a fare gate in order to gain access to the boarding platform. Such a system is slow as it takes time for the gate to open and close between each passenger passing through the fare gate.
In addition, each fare gate allows passage in only one direction until human input changes it. Thus, if higher throughput is desired in such a system, more fare gates (and hence increase floor area for these gates) are required.
One way to overcome the above limitations is to have fare gates that remain open until an invalid fare card is detected. To keep costs down, it is desirable to control and monitor these fare gates with simple, robust embedded sensors systems that are not subject to wear and tear, and which can be inexpensively retrofitted into existing fare gates.